Contact Lens Design & Materials
Three Steps to Lens Comfort
BY DAVID L. KADING, OD, FAAO
As the saying goes: “The more you know, the more you realize how much you don’t know.” With dry eye, this saying seems to be true. The more we understand meibomian gland dysfunction, aqueous deficiency, and inflammatory dry eye, the more we realize the delicate balance that has to be maintained in the ocular surface to protect our contact lens-wearing patients.
In this constant battle of protecting the ocular surface in our contact lens-wearing patients, we have three fronts on which to take the battle.
The first is the treatment of the ocular surface. This needs to be our first priority and should be done in conjunction with lens fitting in patients who have mild discomfort or early dry eye. For patients who have more significant dry eye symptoms or signs, consider advising them to take a break from contact lens wear for a brief time.
Optimize Care Solutions
The second front is to optimize the care solutions that our patients are using. With a significant percentage of patients purchasing store brand solutions, which were formulated prior to silicone hydrogel lenses, it is imperative that we know what care solutions our patients are using. Then, we will be able to upgrade them or switch them to a hydrogen peroxide-based solution when appropriate.
Switching Lens Modalities
The third front relates to switching patients to a new lens material or modality. It should be noted that there are not any contact lenses that have specific approval for the treatment of dry eye. However, eyecare practitioners routinely alter their patients’ lens modality and materials in an effort to decrease their contact lens discomfort, which may in fact be due to a dry eye state.
While this is a fine line for certain, the goal remains that we want to select lens materials that support the ocular surface to its fullest.
Two options that we discuss with our patients are silicone hydrogel and daily disposable lenses.
Silicone Hydrogels Although not new, silicone hydrogel lenses make up the majority of the lens materials that are fit today. Each company’s lenses vary dramatically from each other, and switching between brands can have an impact on patients’ comfort.
As a whole, silicone hydrogels can have a positive impact over their hydrogel counterparts. One study looked at patients who were refit into a silicone hydrogel lens from their prior hydrogel lenses and found a 48% reduction in the number of subjects reporting frequent during-the-day dryness and a 46% reduction of those reporting frequent end-of-the-day dryness (Chalmers et al, 2008).
Daily Disposable Lenses It should be no surprise that the most advanced technology that we have in the contact lens industry is in daily disposable lenses. In the last two years, the advancement of lens materials from several manufacturers has worked to address comfort at a new level.
As this is the case, in our clinic we have elected to move all of our contact lens wearers into daily disposable lenses (this includes toric and multifocal wearers). In fact, year-to-date we are an 83% daily disposable practice. With new materials and the option of silicone hydrogels in the daily disposable modality, there are obvious advantages.
To fix the dry eye, first address the care solution and then consider moving modality and material. With all of the lenses available to us, these three steps can increase the success in our practices, the number of wearers, and, most importantly, the comfortable wearing time of our patients. CLS
For references, please visit www.clspectrum.com/references and click on document #228.
Dr. Kading owns the Specialty Dry Eye and Contact Lens Center in Seattle. He is the co-owner of Optometric Insights with Dr. Mile Brujic. He has received honoraria for consulting, performing research, speaking and/or writing from: Alcon Laboratories, Allergan, Bausch + Lomb, Biotissue, Contamac, Essilor, Nicox, Oculus, RPS Detectors, TearScience, Valley Contax, and ZeaVision. Follow him on Twitter @davekading.